At least 198 people died and 590 people rescued after a ferry capsized in Zanzibar. The ferry, MV Spice, was carrying more than 700 passengers from Zanzibar to Pemba island.

Twitter users including those on the ground in Zanzibar have been updating information about the disaster using the hashtag #ZanzibarBoatAccident.

Soud Hyder from Al Jazeera Kiswahili and Seth Kibet, a crisis mapper and software developer, have set up Ushahidi-based platform for tracking real-time information about the accident. Citizens can submit reports by sending a tweet with the hashtag/s #ZanzibarBoatAccident or #Zanzibar or #Pemba or by filling a form. Ushahidi is an open source project which allows users to crowdsource information.

Amidst confusion about the number of the victims, @ZittoKabwe in Zanzibar updated his follower about the number of casualties:

@zittokabwe: I have just spoken with Zanzibar 1st VP. Rescued stand at 590 and deaths 198 #ZanzibarBoatAccident

@zittokabwe: #ZanzibarBoatAccident amazing! 546 people rescued now. Official – Presindet's Office, just spoke to the PS